design(aws-ecs): Design doc for creating a scheduled ecs task construct

[piradeepk]

Initial Design Doc for a new Scheduled ECS Task Construct

Pull Request Checklist

• Testing
  • Unit test added (prefer not to modify an existing test, otherwise, it's probably a breaking change)
  • CLI change?: coordinate update of integration tests with team
  • cdk-init template change?: coordinated update of integration tests with team
• Docs
  • jsdocs: All public APIs documented
  • README: README and/or documentation topic updated
  • Design: For significant features, design document added to design folder
• Title and Description
  • Change type: title prefixed with fix, feat and module name in parens, which will appear in changelog
  • Title: use lower-case and doesn't end with a period
  • Breaking?: last paragraph: "BREAKING CHANGE: <describe what changed + link for details>"
  • Issues: Indicate issues fixed via: "Fixes #xxx" or "Closes #xxx"
• Sensitive Modules (requires 2 PR approvers)
  • IAM Policy Document (in @aws-cdk/aws-iam)
  • EC2 Security Groups and ACLs (in @aws-cdk/aws-ec2)
  • Grant APIs (only if not based on official documentation with a reference)

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license.

[piradeepk]

Updated the doc with feedback addressed

[clareliguori]

Overall LGTM, I only have nit-picks that doesn't block implementation

[piradeepk]

@awslabs/aws-cdk-team can you please review and merge in the doc?

[piradeepk]

Merging as part of: #2336

[eladb]

would it make sense to decouple the “scheduling” aspect from the task. If a user wishes to execute an ECS task by publishing into an SNS topic for example or as a result of some other CW event rule, what’s their path? I imagined an API where you can simply use an ECS task as an event rule target, which indirectly means that you can also execute it on schedule by simply creating an event rule with a schedule, similarly to Lambda.

[piradeepk]

That sounds like a lower level construct,

would it make sense to decouple the “scheduling” aspect from the task. If a user wishes to execute an ECS task by publishing into an SNS topic for example or as a result of some other CW event rule, what’s their path? I imagined an API where you can simply use an ECS task as an event rule target, which indirectly means that you can also execute it on schedule by simply creating an event rule with a schedule, similarly to Lambda.

Are you thinking about a construct that accepts an existing task definition, instead of constructing a task def or to be able to schedule using different methods (CW Events, SNS events, etc)? The purpose of this construct is to allow customers to create scheduled tasks using cw events (create new tasks, not using existing tasks).

[clareliguori]

To me it sounds like @eladb's suggestion already exists at the L2 level with ecs.Ec2EventRuleTarget:
https://awslabs.github.io/aws-cdk/refs/_aws-cdk_aws-ecs.html#integration-with-cloudwatch-events

I agree with @pkandasamy91: this is intended to be a higher-level construct to make it super simple to do a scheduled task. Most ECS users triggering a task with CloudWatch Events are doing it on a schedule.

[eladb]

Got it. Thanks for the clarification